Pneumatic piano-player and the like.



M. M. KASTNER & G. KATZ.. YNEUMATIG PIANO PLAYER-AND THE LIKE.APPLICATION FILED JUNE 21. 1911.

1,038,761. Patented Sept. 17,1912.

wb qm I,

UNIT D STATES Pa rENT OFFICE.

MACABIUS KAXIMILIAN KASTNER AND CONEAD KATZ, LONDON, ENGLAND; SAID KATZASSIGNOB TO SAID 'KASTNEB.

PNEUMATIC rmNo-rLAYnaANn THE LIKE.

Specification of Letters Patent.

Patented Sept. 17, 1912.

Application filed June 21, 1911. Serial No. 634,528.

7 Margaret street, London, England, have in-- vented certain new anduseful Improvements inPneumatic Piano-Players and the Like, of which thefollowing is a specification, reference Being had to the accompany:

ing drawing. 7

This invention relates to an improvement in pneumatic piano players andthe like and especially to the arrangement fully de-.

scribed and shown in the specification of the pending application for U.S. Letters Patent filed August 2, 1910 Ser. No. 575076.

The object of this invention is to provide means whereby the air ductsleading from the playing and accentuation holes of the tracker board areeasily connected and disconnected respectively and the primary pneumaticof any well known form mostly in practice inserted between each playinghole in the tracker board and the corresponding striking pneumatic valvediaphragm may be omitted. Otherwise there would be two primary neumaticsfor each note, one situated between the playingv hole in the trackerboard and the diaphragm actuating the striking pneumatic valve, and theother situated between the accentuation hole in the tracker board andthe accentuation controlling diaphragm,

In the present invention one primary is employed to admit atmosphericpressure to the accentuation controlling diaphragm as well as to thediaphragm actuating the striking pneumatic valve, means being providedwhereby the passage to the accentuation controlling. diaphragm shall beopened or closed according as'the corresponding accentuation hole iscovered or uncovered.

In the accompanying drawing which illustrates-in cross section apreferred form of our improved pneumatic action, each tone producingopening 1 of a tracker bar 2 is by tube 3' connected to a primary 3,from which a duct 4 leads to a diaphragm 5 tlat controls the'hammeractuating bellows 6. The air is withdrawn from the latter throughopenings a, b, aof which zopenings a and b are adapted to be closed by adisk d controlled bya diaphragm 10", while tpening 0 permanently open.Duct 4 communicates through branch 7 with a small junction chamben 8,while the latter is in turn, by.,a'

duct 9,-connected to the hollow space 10 formed behind the accentuationcontrolling diaphragm 10*, which is located within a vacuum chamber 14.Ducts 7 and 9 are adapted to be closed by a diaphragm 11, which dividesthe chamber into two parts, both the openings being in one part of thechamber. The part of the chamber on the other side of the diaphragm isconnected by Y wayof a duct- 12 with the accent-nation hole 13 in thetracker board 2 and is normally exhausted so that when the playingholein the tracker board'is uncovered the atmospheric air pressureforces the diaphragm away from the openings 7 and 9 and air passes tothe accentuation controlling diaphragm as well as to the strikingpneumatic diaphragm so that the normal or soft blow is struck. This isif the accentuation hole in the tracker board is covered. Should it beopen, then the air pressure admitted to closed. The latter therefore isdeflated, and

the vacuum existing Within chamber 14 retracts disk d so as to openports a. and b and effect a powerful collapse of the bellows,.

whereby the desired emphasis of the tone is obtained.

Having fully described the features of the invention what we claim is:

1; In an expression device for pneumatic pianos and similar musical.instruments, a tracker bar having a tone producing p'erforation and atone accentuating perforation, a vacuum chamber,,hammcr actuatingbellows, a diaphragm controlling communication between said chamber andbellows, a

first duct cooperating-with the tone producing perforation andcontrolling said diaphragm, a tone accentuating dia hragm,

means controlled thereby for esta lishing additional communicationbetween the chamber and *bellows, a second duct controlling said lastnamed diaphragm, and means controlled by the tone accentuatingperforation for establishingf c'ommunication between both of said ducts.

2. .In an expression device for pneumaticpianos and similar musicalinstruments, a 110 tracker bar having a tone producing per foratiori,and a tone accentoatirig' per-fora tion, a vacuum chamber, a first ductcooperating with the tone producing perforaa vacuum chamber, hammeractuating tion, a first diaphragm ritermedia te said chamber and duct,hammer-actuating heilows, means coritroiied by said first diaforestablishing communication between said chamber bellows, atore-acceritriatiog second diaphragm, means cootroiied toy said seconddiaphragm ior establishing additioriai communication between the chamberand heilows, a second duct controlling said second diaphragm, anda thirddiaphragm 'controiled by the tone accentuating perforation forestablishing communication between both of said ducts,

in testimony whereof we have afifixed our signatures in the presence cittwo subscribing' witnesses this 8th day of June 1911.

MAG LBJLUQ LZAKZLKHATEI KASEHEE. UGNRAE W itnesses it. it ssracorr, H.D, JAMEEON.

flootes oi thlormteat he obtained tor five cent Washington, E, 6.

Gommssioaer of 5 each, addressing the

